I'd really appreciate some feedback on a fuel delivery issue:

I had a Vishnu Stage II installed on my '03 WRX sedan about 1,200 mi. ago (12/29/03). This package consists of vf34 turbo, STi 565cc injectors, and Walbro GSS341 255 lph fuel pump + ECUTEK reflash. This last Sunday the Walbro started "whining" rather loudly and then died about 100 mi. later during a canyon run. I chalked it up to a defective pump so I purchased a replacement Walbro 341 and had it installed by a Subaru mechanic. The new pump was quiet as a church mouse and seemed to work fine around town. This morning I took the car for a shakedown cruise after filling up with 91 octane and spiking it with 1 gal. of toluene. I drove hard for about 100 mi. and then I noticed that the car started to cut out at about 6K rpm in 4th gear (~120 mph). Shortly after that when I slowed down to freeway speed, I could hear the pump making a lot of noise again and then it got worse and I was unable to sustain anything over 60 mph without the motor falling on it's face. I had to pull over at one point because the car wouldn't run at all and started throwing CEL's. The pump seemed to perk back up a bit after I stopped the motor for a few minutes so I limped my way back home, having to stop a few more times in the process.

So, here I am again back at step one. Could someone tell me where to start troubleshooting this? Has anyone had or heard of a similar problem? I've read about lots of people running their cars successfully with toluene but could it be a factor--or is it an electrical issue? I seriously doubt that I got two bad Walbro fuel pumps. I'm getting pretty frustrated

TIA,
Jim

 

Thanks Mike, Andy, and MexicanPizza for your input. I have reused the stock "sock", the pump assembly is properly installed, and the pump itself is ziptied as well. The gentleman who is working on this--the same one who replaced the second Walbro 341--is a very competent certified master Subaru technician. I will call the installer for Vishnu to pick his brain but I know he has done over two hundred Stage II installs and knows what he is doing. I'll also try to get in touch with Walbro.

Please keep the feedback coming--I'll take all the input I can get!

Thanks fellas,

Jim

 

I was told the ground in question attaches to the intake(engine compartment)on the drivers side, attached with a 12mm bolt.

 

There is a ground for the pump in the trunk, and as I understand it, a ground for the fuel modulator in the engine compartment.

 

Yup,
I've got a 342 coming from MPJ performance..should be here by Tues. I hope I can return the 341's and find the culpret. Troubleshooting can be such a PITA I'll post the resolution to this dilemma when I figure it out. If this could happen to me, it could happen to anybody

 

I live at 616 8th St.
Stop by anytime. My Subie's usually right outside my apartment in the alley
P.S.
You know your're halulin' *** when your're coming into Coronado and you hit that hair pin curve that starts just past mid-span